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AP EAMCET201823 Apr 2018Morning ShiftMathematicsSequences and SeriesActual

If (1+ 3 1 ) (1+ 5 4 ) (1+ 7 9 ) (1+ 2 n+1 n^2 )=121 , then n=

Options

  1. A11
  2. B10
  3. C9
  4. D8

Correct answer

B. 10

Step-by-step solution

We have, array ll (1+ 3 1 ) (1+ 5 4 ) (1+ 7 9 ) (1+ 2 n+1 n^2 )=121 (4) ( 9 4 ) ( 16 9 ) ( n^2+2 n+1 n^2 )=121 n^2+2 n+1=121 (n+1)^2=121 n+1=11 n=10 array

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